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Bisphenol-C epoxy crotonate resin was synthesized by reacting 8.09g epoxy resin of bisphenol-C, and 2.15g crotonic acid using 25 mL 1,4-dioxane as a solvent, and 1 mL triethylamine as a catalyst at reflux temperature for 1-6 h. Solid epoxy crotonate (ECCR) is highly soluble in common organic solvents. ECCR was characterized by its acid (24.5-1.5 mg KOH/g) and hydroxyl (504.5-678.4 mg KOH/g) values. The structure of ECCR is supported by FTIR and 1HNMR spectroscopic methods. A DSC endothermic transition at 229oC indicated melting followed by thermal polymerization of ECCR. ECCR is thermally stable up to 320oC and follows three-step degradation kinetics. The first step followed first-order degradation kinetics, while the second and third steps followed one-half-order degradation kinetics. High values of kinetic parameters suggested the rigid nature of the crosslinked resin. Jute-, Glass- and Jute-natural fiber-ECCR composites showed moderate tensile strength, flexural strength, electric strength, and volume resistivity due to the rigid nature and poor interfacial adhesion of the composites. J-ECCR and G-ECCR composites showed high water absorption tendency and excellent hydrolytic stability against water, 10% aq. HCl and 10% aq. NaCl and even in boiling water. Mechanical and electrical properties and water absorption tendency of the composites indicated their usefulness as low load-bearing housing and insulating materials. They can also be utilized in harsh environmental conditions. [ABSTRACT FROM AUTHOR]

Polyester polyols(EMCRA, EMCLA, EMCOA and EMCR) of epoxy resin of 1, 1'- bis (3-methyl-4- hydroxy phenyl) cyclohexane (EMC, EE 835) and their polyurethanes (EMCRAT, EMCLAT, EMCOAT and EMCRT) have been synthesized and characterized by acid and hydroxyl values, IR, 1HNMR, GPC, DSC and TGA at 10°C/min heating rate in nitrogen atmosphere. Epoxy polyester polyols possess excellent solubility in common solvents and thermal stability (270-295°C) and followed either single or multistep decomposition. They followed either integral or fractional order degradation kinetics. The associated kinetic parameters have been determined and discussed. Polyurethanes coating remained intake in water and saline environments without any physical and chemical change but they failed in acidic environments. [ABSTRACT FROM AUTHOR]